When have you guys changed your oil separator

Hi. Am approaching the 100K mark on my 08 E90 M3. I will be doing spark plugs soon and am thinking of changing out the oil separators (Crankcase Pressure Regulator valve...p/n 11157848155).

https://www.ecstuning.com/b-genuine-bmw-parts/crankcase-pressure-regulator-valve-priced-each/11157848155/

Was wondering have people done proactive replacement of the oil separators ...and if so at what mileage...and any symptoms. - Also, how easy is it to pull the oil separators. From the diagrams, they appear connected to valve cover via 4 torx screws....and also some grommets?

It's just the 4 torx screws to replace, but you don't need it unless you have excess oil consumption/bad idle/sluggish performance....

Are they any wearable components in it? I would think just soaking them in decreaser and a good rinse would be sufficient.

Leonardo629 wrote

It's just the 4 torx screws to replace, but you don't need it unless you have excess oil consumption/bad idle/sluggish performance....

Thanks Leonardo.

One more question....can I pull this directly off the valve cover WITHOUT lifting the plenum cover up? Trying to see if I can get to the oil separator without fussing with the plenum.

As for why I am considering changing the separator, am currently using 1 liter every 1.2K mi. It's been consistent ever since I bought the car at 80K miles. No leaks, stumbling, or issues with the car........but thought I'd go ahead and try replacing the oil separators when I do my spark plugs next month.

It's connected to the plenum, so plenum needs to come off first, then 4 torx screws....new separators come with new o-rings.

Tip:

If you remove the separator from the valve cover, check the sealing surface before just slapping on a new one. A lot of times (especially on higher mile ones like yours), peeling off the separator will also pull off some of the valve cover coating.

If that happens you'll need to add a tiny bit of grey gasket maker to the surface if you don't want to introduce oil leaks there.

And yes. Though the separator is mostly just a series of chambers, there is a silicone rubber valve on it that can get lost or lose its proper seal which necessitates replacement. At your mileage, it's a good idea to replace while you're in there.

Dean - Hi.....thanks for feedback and tips. Would you recommend perhaps using a blow dryer on low setting to soften up the gasket before trying to yank off the separator?

Oh btw, the center console I got off you worked perfectly. Thanks!

deansbimmer wrote

Tip:

If you remove the separator from the valve cover, check the sealing surface before just slapping on a new one. A lot of times (especially on higher mile ones like yours), peeling off the separator will also pull off some of the valve cover coating.

If that happens you'll need to add a tiny bit of grey gasket maker to the surface if you don't want to introduce oil leaks there.

And yes. Though the separator is mostly just a series of chambers, there is a silicone rubber valve on it that can get lost or lose its proper seal which necessitates replacement. At your mileage, it's a good idea to replace while you're in there.

kimiraikkonen wrote

Dean - Hi.....thanks for feedback and tips. Would you recommend perhaps using a blow dryer on low setting to soften up the gasket before trying to yank off the separator?

Oh btw, the center console I got off you worked perfectly. Thanks!

Great to hear!

To answer your question, heat probably won't do much for softening anything up since the part has seen so many high heat cycles that the o-ring and valve cover coating have literally glued themselves together.

Let us know how it goes!

was there any oil consumption decrease after changing separators?

toolshed wrote

was there any oil consumption decrease after changing separators?

Hi. I finally got around to changing it just last week (when I did my Bank 2 throttle actuator). So will let you know if there's any change in consumption.

In case you are interested, here's the condition of one of the oil separators (after 100K mi). I didn't notice any blocked holes or ports, but definitely some buildup over time.

kimiraikkonen wrote

Hi. I finally got around to changing it just last week (when I did my Bank 2 throttle actuator). So will let you know if there's any change in consumption.

In case you are interested, here's the condition of one of the oil separators (after 100K mi). I didn't notice any blocked holes or ports, but definitely some buildup over time.

Hi! Thanks for the info!

Was there some unusual sound changes after shifting new seps? Maybe you had any whistling that gone then?

And how's the valve cover coatings from that Dean's tip above?

toolshed wrote

Hi! Thanks for the info!

Was there some unusual sound changes after shifting new seps? Maybe you had any whistling that gone then?

And how's the valve cover coatings from that Dean's tip above?

Hi. As for sounds, didn't notice anything different. As you know, our S65 always makes interesting noises..... =)

I did change one of my throttle actuators when I did the separators, so did notice a reduction in throttle noise...but probably unrelated to the separator change.

As for the coating peeling issue that Dean described above.....a few valve cover flakes were attached to the old separator.....I just did a good wipe down and installed the new separators. The 4 bolts do hold it down quite well, so the few mils of paint that flaked off shouldn't make a difference.

Will report back soon on the oil consumption. Am hoping this improves things.

well, my new seps works much better now)

old ones were dead - intake manifold had a specific oil odour.
and internal surfaces of throttle housings (I mean yellow circles) had burnt oil sludge

kimiraikkonen wrote

toolshed wrote

Hi! Thanks for the info!

Was there some unusual sound changes after shifting new seps? Maybe you had any whistling that gone then?

And how's the valve cover coatings from that Dean's tip above?

Hi. As for sounds, didn't notice anything different. As you know, our S65 always makes interesting noises..... =)

I did change one of my throttle actuators when I did the separators, so did notice a reduction in throttle noise...but probably unrelated to the separator change.

As for the coating peeling issue that Dean described above.....a few valve cover flakes were attached to the old separator.....I just did a good wipe down and installed the new separators. The 4 bolts do hold it down quite well, so the few mils of paint that flaked off shouldn't make a difference.

Will report back soon on the oil consumption. Am hoping this improves things.

Did oil consumption change?

I believe mine is producing a very minor oil leak on the driver side. The oil level drops just one level within the last 500-1000 miles before an oil change is due. I do changes at 5k intervals so no changes in consumption from what I can tell. I noticed the leak when I was doing spark plugs at around 30k miles and since then nothing major has progressed in terms of leaks. The car is at 36k miles now. Passenger side looks dry. Does the replacement part on ECS come with the new rubber gaskets already applied?

Bump and disclaimer for anyone doing this, the torx screws are ONE TIME USE!
Make sure you have new ones before you start, or else you will be like me and have a 30 minute job turn into a 2-3 hour job! 🤠

Fenbrazier wrote

Bump and disclaimer for anyone doing this, the torx screws are ONE TIME USE!
Make sure you have new ones before you start, or else you will be like me and have a 30 minute job turn into a 2-3 hour job! 🤠

Aluminum fasteners always one time use.

Brandoch wrote

Aluminum fasteners always one time use.

Yeah one time use. Mine are also covered blue and I think that's supposed to be another indicator to replace if removed?

So does the new separator come with fresh gaskets? No one answered lol

Reddevils7 wrote

Yeah one time use. Mine are also covered blue and I think that's supposed to be another indicator to replace if removed?

So does the new separator come with fresh gaskets? No one answered lol

Yes about the bolts, do not know about the gasket.